Andy Gock

Just some bloke in Australia makin' stuff.

Latest Articles

GPG Cheat Sheet

25 July, 2020 - 4 min read

For GPG versions 2.x only. List keys List public keys List all secret keys List public or secret keys, but show subkey fingerprints as well The key ring location is normally shown on the first line on stdout. Use different key ring List keys but use a different home directory for one command only… Read more

Using Let's Encrypt with internal web servers (without DNS challenge)

05 July, 2020 - 6 min read

TL;DR Use internet facing domain on an internal network, I normally use subdomains for this. Domain must have a DNS A record pointing to a public facing web server so Let's Encrypt can find it for the HTTP-01 challenge. This can be served as an empty site or just as a 404 response. Remote VPS uses… Read more

Protecting web sites with NGINX subrequest authentication

30 June, 2020 - 4 min read

TL;DR Protecting a web site with NGINX by using authentication server via a subrequest. Use in NGINX conf. When user requests protected area, NGINX make internal request to . If 201 is returned, protected contents are served. Anything else, NGINX responds with 401. is reverse proxied to Express… Read more

Netlify vs Vultr VPS hosting speed from Australia

28 April, 2020 - 2 min read

I've been comparing some load speeds from a variety of different web hosting companies. I started out by trying out the free tier of Netlify to compare how the performance is compared with my usual Vultr VPS service. After seeing that the Netlify load times was almost 10x longer than from the VPS… Read more

Convert multiple images to searchable PDF (OCR) with free command line tools

26 April, 2020 - 2 min read

In this example, we'll show how to convert multiple PNG images to a multi page searchable PDF file. We'll use the following command line tools: ImageMagick for converting PNGs into multi page TIFF and PDF files. Tesseract OCR, an open source OCR engine. PDFtk Free for overlay joining of PDF files… Read more

Start a simple React JS app with Parcel bundler

11 August, 2019 - 3 min read

Here's how to get started with a simple hello world React Javascript app using Parcel. We're going to be using a global install of Parcel here. Install Parcel Install parcel globally The advantage if you install it globally is that is only 4MB and 100 or so files. on the other hand will download… Read more

Loading icon fonts locally when using Ant Design React framework (instead of AliCDN)

05 August, 2018 - 1 min read

Don’t use Alibaba’s CDN! By default, when using the Ant Design ReactJS UI framework, icon fonts are loaded from China’s Alibaba Cloud CDN. This may be undesirable behaviour. You might prefer to have a web site that does not call home when you load a page, or leak IP addresses to a third party. You… Read more

Set up a signage or kiosk machine with Debian 9 Linux

26 June, 2018 - 2 min read

Installation Install Debian with . Use MBR and create a single root partition filling the entire disk. Choose minimal with no graphical desktop environment. Only choose standard system utilities. Create the default root user and a separate user with username . Install the following packages as root… Read more

Virtual Box Tips

16 April, 2017 - 2 min read

Backing up VirtualBox virtual machine Just make a copy of the and files. Reducing disk space of dynamic disks This doesn't work for encrypted disks. On client virtual machine: For Windows Defragment disk, e.g Zero free space, e.g (sdelete is part of SysInternals) For Linux (mounted) until there… Read more

Moving Virtual Box VDI files

16 April, 2017 - 2 min read

Note This works with encrypted VDI disks. The virtual machine must be shut down before proceeding. Backup first! Backup all the and files. Ths is very important! If you're using encryption, these keys are inside the vbox file so make sure you back this up somewhere safe. From now on we don't touch… Read more

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